Bridgehampton resident Dereyk Patterson stood in his East Hampton fine woodworking shop, preparing to share an unsettling memory of his late stepfather.

He slipped on blue latex gloves and pulled a skull—some teeth still intact, the rest in a plastic Ziploc bag—out of a tote bag and placed it on his work table. Two femur bones wrapped in foil followed.

The arrangement eerily resembled the makings of a skull and crossbones. The bones had a polished, brownish tint, almost as if they had once been shellacked or coated with polyurethane.

His stepfather acquired the bones while serving as a U.S. Army helicopter pilot in the Vietnam War. The bones passed down to Mr. Patterson in 2003 after his stepfather died in an accident the year prior.

The story, as relayed to Mr. Patterson, is that the remains are that of a Viet Cong soldier. For years, he has been committed to returning the bones to Vietnam to remedy what some might consider a dishonorable act.

“It is the right thing to do,” he said.

The Tale of the Bones

The story goes as follows:

Stephen Patterson, a warrant officer in the Army’s 25th Infantry Division, who was awarded a Silver Star, was completing his third and final tour in Vietnam, in the southern province of Tay Ninh.

While flying, he spotted the body of a Viet Cong soldier in a rice paddy, and landed to take a look. The soldier wore web gear, which perhaps suggested a high rank.

“I guess that was the impetus for taking the bones,” Mr. Patterson said of his stepfather. “The psychology of it makes sense,” he went on to say, given the wartime horrors that U.S. soldiers, and his stepfather in particular, experienced. “But at the end of the day, it’s a dishonorable thing.”

The elder Mr. Patterson didn’t act immediately: He eyed the body on flights, waiting for it to decompose a bit before going back and taking the bones.

It was nearing Christmas 1968 when he had the bones shipped in a box to his aunt’s house in Riverside, California. Supposedly, the box was placed under a Christmas tree, thought to be a gift. But when the dog circled the tree, his aunt, Ruth Ketner, figured it might contain perishables. She opened the box and, to her surprise, saw the remains, with some flesh still on them. Ms. Ketner, a nurse, bleached the bones and put them on the roof to dry out.

Ms. Ketner gave him the bones when he returned to the country, and he took them when he moved to Garrison, New York. He later worked as a bush pilot in Venezuela, until he died in October 2002 in an accident—his plane crashed into the side of a mountain due to a miscommunication while en route to Caracas.

Following his stepfather’s death, Mr. Patterson retrieved the bones from Garrison, and brought the bones to Northampton, Massachusetts, where he lived then. Now, the bones reside in Mr. Patterson’s garage in Bridgehampton.

Mr. Patterson, now 50, never learned why exactly his stepfather took the remains, but said he had no reason to believe the story he had been told was untrue.

The bones were referenced in a thesis, “Dark Trophies: Hunting and the Enemy Body in Modern War” by Simon Harrison, which discusses the taking of body parts of enemies as trophies in contemporary warfare.

Mr. Patterson said he wished he had asked his stepfather more questions about the remains, such as whether he took any sort of identification from the soldier.

“We were a very uncommunicative family,” he said.

After Failed Attempts, A Chance Meeting

Soon after his stepfather’s death, Mr. Patterson tried to return the bones to Vietnam via the U.S. Army, but was discouraged by the uncertainty of what would happen to them.

“Basically, the email said, ‘Put the remains in a box, mark it accordingly, and send it to us,’” he said. “It seemed so vague. My read on the whole thing was that they were just going to end up in a storage facility, and it just didn’t sit well with me.”

Mr. Patterson tried again in 2005, calling the U.S. embassy in Ho Chi Minh City. But this time he was discouraged by miscommunication, failing to get across what he was trying to do.

His last-ditch effort was to go to the local police for some guidance, but he decided against it. “I thought about that one and could see myself in handcuffs,” he said.

Since then, Mr. Patterson had been left with no leads on how to repatriate the remains. That is, until one day a few weeks ago, when he received a call at his woodworking shop from someone who needed a piece of wood cut.

Tim McCarty, a police sergeant from St. Paul, Minnesota, was staying in East Hampton and working on his vacation spot. Mr. Patterson agreed to help, and the two got to talking.

Mr. Patterson felt he could trust Mr. McCarty and so told him the story of the bones—perhaps he could help, given his background.

Mr. McCarty did some searching online and found Bioglobe, a Hamburg-based laboratory that developed “Project 150,” a mission in conjunction with the Vietnamese government to genetically identify hundreds of thousands of victims of the Vietnam War, recovered from mass graves, and return them to their families so that they can be buried in accordance with their culture.

Mr. Patterson quickly contacted Bioglobe and was put in touch with its founder, Wolfgang Hoeppner, Ph.D.

“It’s crazy the way the world works sometimes,” Mr. McCarty said.

A New Plan

Mr. Hoeppner was at first skeptical of the tale because he has seen cases in which people have claimed to have bones that turned out to be fake, and others who make outrageous claims, such as saying they can speak to the dead.

Mr. Patterson sent him a link to a radio piece from 2003 about Mr. Patterson’s first attempt to return the bones as way to help verify the story in some way. “It’s well known that people take trophies from war victims and keep them for I don’t know what reasons,” Mr. Hoeppner said.

Mr. Hoeppner made some calls to the Vietnamese embassy in Washington, D.C., to learn the proper channels for returning the bones. “You can’t just put bones in a travel bag,” he said.

It was recommended that they be given to the embassy—but before that can happen some verification needs to be made.

“My suggestion is to find an anthropologist to look at the bones and verify that these three bones belong together,” he said in phone interview, as it is possible the bones could be from two or three different skeletons. He said an anthropologist could confirm that the bones are real and determine by the skull whether the remains belonged to someone of Asian descent, as well as the age and gender.

There is no guarantee that the bones will be identified after they are sent back to Vietnam, according to Mr. Hoeppner.

Also, a bank of genetic data must be filled through blood samples to compare DNA from bones to that of the living. It that could take years, and it is not certain that any relatives will have contributed to that bank.

To extract DNA from a bone, Project 150 would conduct a process in which a fingertip-sized piece is cleaned, then ground down to a powder. From that powder, calcium is extracted and run over with a silica gel to release the DNA.

And while Project 150 is a way to achieve closure to the families of war victims in Vietnam, it is also a way for Mr. Patterson to find closure in his relationship with the man who he viewed as his real father.

“It’s closure for me as well, because I know the right thing happened,” he said.

He recalled his childhood in Venezuela with his stepfather, who adopted Mr. Patterson after marrying his mother, Jeanne. The two would spend time together in planes, flying all over the country, as his stepfather worked as a bush pilot. “It was an amazing life,” he said.

“As a father, he was great. But as a role model, as the guy that you want giving your kids the morals on how to live through life, you didn’t want him, because he was a very anti-establishment person,” he said. “He just didn’t know how to go by the rules.”